Dynamic compensation of a phased array RFID reader

1. A method for configuring an RFID reader having an antenna array, the antenna array being housed within an RFID reader enclosure of the RFID reader, the method comprising: exciting, via a controller of the RFID reader, a reference antenna element of the antenna array; emitting, via the reference antenna element, an emitted signal, the emitted signal having an emitted signal amplitude, emitted signal frequency, and emitted signal phase; receiving the emitted signal via a receiver antenna element of the antenna array; generating, via the receiver antenna element, a received signal, the received signal having a received signal amplitude and a received signal phase; determining, via a processor, a phase shift of the received signal relative to the emitted signal; determining, via the processor, a phase-shift error, the phase-shift error being determined from a determined phase shift and an expected phase shift; and configuring the RFID reader to compensate for the phase-shift error associated with the receiver antenna element in response to receiving an RFID tag signal.

2. The method of claim 1 , wherein the reference antenna element is a radio frequency antenna element.

3. The method of claim 1 , wherein the receiver antenna element is a radio frequency antenna element.

4. The method of claim 1 , wherein the emitted signal frequency is at least one of an extremely low frequency, a super low frequency, an ultra low frequency, a very low frequency, a low frequency, a medium frequency, a high frequency, a very high frequency, an ultra high frequency, a super high frequency, an extremely high frequency, or a tremendously high frequency.

5. The method of claim 1 , wherein the phase shift is determined by the difference between the received signal phase and the emitted signal phase.

6. The method of claim 1 , wherein the phase-shift error is determined by the difference between the determined phase shift and the expected phase shift.

7. The method of claim 1 , wherein the emitted signal amplitude is a modulated emitted signal amplitude.

8. The method of claim 1 , wherein the receiver antenna element is one of a plurality of receiver antenna elements; and further comprising: receiving the emitted signal at each of the plurality of receiver antenna elements; generating, via each of the plurality of receiver antenna elements, a plurality of received signals, each received signal of the plurality of received signals having a corresponding received signal amplitude and received signal phase; determining, via the processor, a plurality of phase shifts relative to the emitted signal, wherein each of the plurality of phase shifts corresponds to one of the received signals of the plurality of received signals; determining, via the processor, a plurality of phase-shift errors, each of the plurality of phase-shift errors corresponding to one of the plurality of receiver antenna elements, and each of the plurality of phase-shift errors being determined by a corresponding determined phase shift, of a plurality of determined of phase shifts, and an expected phase shift of a plurality of expected phase shifts; and configuring, in response to receiving an RFID tag signal, the RFID reader to compensate for each of the phase-shift errors of the plurality of phase-shift errors associated with each of the corresponding receiver antenna elements of the plurality of receiver antenna elements.

9. The method of claim 8 , further comprising: receiving, via the plurality of receiver antenna elements of the antenna array, an RFID tag signal, the RFID tag signal having a corresponding RFID tag signal amplitude, and RFID tag signal phase at each of the plurality of receiver antenna elements; compensating, via the RFID reader, the phase shift of the RFID tag signal received at each of the plurality of receiver antenna elements; analyzing, via the processor, a compensated RFID tag signal to determine a plurality of compensated RFID tag signal phases received, the plurality of compensated RFID tag signal phases corresponding to the plurality of receiver antenna elements; and determining, via the processor, an angle of arrival of the RFID tag signal from the plurality of compensated RFID tag signal phases received at the plurality of receiver antenna elements.

10. The method of claim 8 , further comprising: determining, a second reference antenna element from the plurality of receiver antenna elements; exciting, via the controller, the second reference antenna element; emitting, via the second reference antenna element, a second emitted signal, the second emitted signal having a second emitted signal amplitude, second emitted signal frequency, and second emitted signal phase; receiving the second emitted signal via a second plurality of receiver antenna elements, wherein the second plurality of receiver antenna elements comprises the first reference antenna element and the set of the plurality of receiver antenna elements excluding the second reference antenna element; generating, via the second plurality of receiver antenna elements, a plurality of secondary received signals, each secondary received signal of the plurality of secondary received signals having a corresponding received secondary signal amplitude and received secondary signal phase; determining, via the processor, a plurality of secondary phase shifts relative to the second emitted signal, wherein each of the plurality of secondary phase shifts corresponds to one of the second received signals of the plurality of secondary received signals; determining, via the processor, a plurality of secondary phase-shift errors each corresponding to a receiver element of the second plurality of receiver antenna elements, and the plurality of secondary phase-shift errors being determined by a corresponding determined phase shift of a plurality of secondary determined phase shifts and a secondary expected phase shift of a plurality of secondary expected phase shifts; and configuring, in response to receiving an RFID tag signal, the RFID reader to compensate each of the second plurality of receiver antenna elements for each of the corresponding secondary phase-shift errors of the plurality of secondary phase-shift errors.

11. A system for configuring an RFID reader with an antenna array, the antenna array being housed within an RFID reader enclosure of the RFID reader, comprising: a plurality of antenna elements, each of the plurality of antenna elements being part of the antenna array; a phase shifter, configured to shift the phase of an electrical signal; a non-transitory memory configured to store data and computer readable instructions; a controller communicatively coupled to the plurality of antenna elements, wherein the controller is configured to excite the antenna elements, and receive excitations from the antenna elements; and a processor configured to execute the computer readable instructions to cause the system to: excite, via the controller, a reference antenna element, the reference antenna element being one of the antenna elements of the plurality of antenna elements of the antenna array; emit, via the reference antenna element, an emitted signal, the emitted signal having an emitted signal amplitude, emitted signal frequency, and emitted signal phase; receive the emitted signal via a receiver antenna element, the receiver antenna element being one of the plurality of antenna elements of the antenna array; generate, via the receiver antenna element, a received signal, the received signal having a received signal amplitude and a received signal phase; determine, via the processor, a phase shift of the received signal relative to the emitted signal; determine, via the processor, a phase-shift error, the phase-shift error being determined from a determined phase shift and an expected phase shift; and configure, in response to receiving an RFID tag signal, the RFID reader to compensate for the phase-shift error associated with the receiver antenna element.

12. The system of claim 11 , wherein the reference antenna element is a radio frequency antenna element.

13. The system of claim 11 , wherein the receiver antenna element is a radio frequency antenna element.

14. The system of claim 11 , wherein the emitted signal frequency is at least one of an extremely low frequency, a super low frequency, an ultra low frequency, a very low frequency, a low frequency, a medium frequency, a high frequency, a very high frequency, an ultra high frequency, a super high frequency, an extremely high frequency, or a tremendously high frequency.

15. The system of claim 11 , wherein the phase shift is determined by the difference between the received signal phase and the emitted signal phase.

16. The system of claim 11 , wherein the phase-shift error is determined by the difference between the determined phase shift and the expected phase shift.

17. The system of claim 11 , wherein the emitted signal amplitude is a modulated emitted signal amplitude.

18. The system of claim 11 , wherein the receiver antenna element is one of a plurality of receiver antenna elements; and wherein the computer readable instructions further cause the system to: receive the emitted signal at each of the plurality of receiver antenna elements; generate, via each of the plurality of receiver antenna elements, a plurality of received signals, each received signal of the plurality of received signals having a corresponding received signal amplitude and received signal phase; determine, via the processor, a plurality of phase shifts relative to the emitted signal, wherein each of the plurality of phase shifts corresponds to one of the received signals of the plurality of received signals; determine, via the processor, a plurality of phase-shift errors, each of the plurality of phase-shift errors corresponding to one of the plurality of receiver antenna elements, and each of the plurality of phase-shift errors being determined by a corresponding determined phase shift, of a plurality of determined of phase shifts, and an expected phase shift of a plurality of expected phase shifts; and configure, in response to receiving an RFID tag signal, the RFID reader to compensate for each of the phase-shift errors of the plurality of phase-shift errors associated with each of the corresponding receiver antenna elements of the plurality of receiver antenna elements.

19. The system of claim 18 , wherein the computer readable instructions further cause the system to: receive, via the plurality of receiver antenna elements of the antenna array, an RFID tag signal, the RFID tag signal having a corresponding RFID tag signal amplitude, and RFID tag signal phase at each of the plurality of receiver antenna elements; compensate, via the RFID reader, the phase shift of the RFID tag signal received at each of the plurality of receiver antenna elements; analyze, via the processor, a compensated RFID tag signal to determine a plurality of compensated RFID tag signal phases received, the plurality of compensated RFID tag signal phases corresponding to the plurality of receiver antenna elements; and determine, via the processor, an angle of arrival of the RFID tag signal from the plurality of compensated RFID tag signal phases received at the plurality of receiver antenna elements.

20. The system of claim 18 , wherein the computer readable instructions further cause the system to: determine, a second reference antenna element from the plurality of receiver antenna elements; excite, via the controller, the second reference antenna element; emit, via the second reference antenna element, a second emitted signal, the second emitted signal having a second emitted signal amplitude, second emitted signal frequency, and second emitted signal phase; receive the second emitted signal via a second plurality of receiver antenna elements, wherein the second plurality of receiver antenna elements comprises the first reference antenna element and the set of the plurality of receiver antenna elements excluding the second reference antenna element; generate, via the second plurality of receiver antenna elements, a plurality of secondary received signals, each secondary received signal of the plurality of secondary received signals having a corresponding received secondary signal amplitude and received secondary signal phase; determine, via the processor, a plurality of secondary phase shifts relative to the second emitted signal, wherein each of the plurality of secondary phase shifts corresponds to one of the second received signals of the plurality of secondary received signals; determine, via the processor, a plurality of secondary phase-shift errors each corresponding to a receiver element of the second plurality of receiver antenna elements, and the plurality of secondary phase-shift errors being determined by a corresponding determined phase shift of a plurality of secondary determined phase shifts and a secondary expected phase shift of a plurality of secondary expected phase shifts; and configure, in response to receiving an RFID tag signal, the RFID reader to compensate each of the second plurality of receiver antenna elements for each of the corresponding secondary phase-shift errors of the plurality of secondary phase-shift errors.